It has become common to electronically monitor and charge vehicles entering or moving on toll highways by means of an interrogator and transponder. The interrogator is a transmitter/receiver device owned by the highway operator that communicates with transponders that are installed within the vehicles. One or more of such interrogators are installed at the entrance or at specific locations along sections of the highway. Only upon receipt of the interrogation signal, the vehicle transponder responds by transmitting the identity of the car (or any other unique signal enabling the identification of the car) to the interrogator. Upon receipt and processing of the transponder signal, the highway operator can charge the car owner for using the highway.
The interrogators and transponders usually operate by means of electromagnetic signals, but the present invention is not limited to any type of communication means, for example, optical, ultrasonic, etc. Most commonly, the interrogators and transponders operate by means of RF signals, and therefore the transponder is sometimes referred to as “RF ID”. Furthermore, there have been developed specific protocol standards for such interrogator-transponders communication, for example ASTM V6.
Generally, the vehicle transponder is in a form of an electronic card or in a form of a small circuit which is mounted within a closed, sometimes molded casing. The transponder is generally positioned by the driver at the internal side of the front vehicle window.
Generally, the transponders operate in an “always active” mode, i.e., there is no switch for turning them OFF. In order to save energy of the transponder battery, the transponder is designed to stay in “standby” mode during most of the time, and they switch to “transmit” mode only upon receipt of an interrogation signal. During the “standby” mode, the energy consumption is minimal. When the battery becomes weak or empty, the driver either replaces the battery or the whole transponder unit with the battery.
In some locations in the US regulations have been effected which allow drivers who carry passengers above a specific number to use dedicated lanes (HOV—High Occupancy Vehicle). Recently, in some locations in the US regulations have been effected which allow drivers who carry passengers under specific number to use said same dedicated lanes by paying toll. Such a manner of using the toll lanes requires the driver to switch his transponder between an “active” mode (when the number of passengers in the vehicle is below the limit, and he has to pay for using the lane) and a “non-active” mode (when the number of passengers is above that limit, and he does not to pay for using the lane.
As said, the conventional transponders operate in an “always active” mode, and they are not provided with a switch for its deactivation. One possible way which has been proposed for enabling a driver to deactivate the transponder is to use masking bag. More particularly, it has been proposed to provide each driver with a masking bag made of metal. When the driver wishes to deactivate the transponder, he is required to detach the transponder from its location on the window, and to put it in the masking bag. The masking bag masks and prevents electromagnetic signals from the interrogator to reach the transponder, or signals leaving the transponder to reach the interrogator. However, such an approach is not safe, as it requires the driver to perform actions that divert his attention from the highway.
Another approach that has been proposed is to provide within the transponder a simple ON-OFF switch accessible to the driver, that will be turned ON or OFF by the driver according to necessities. Although this option is possible, it also not safe, as it requires a significant attention by the driver. The status of the switch, which has to be relatively small, cannot be easily observed by the driver. Also, the location of the transponder may make it hard for the driver to determine the status of the switch. These size and location limitations, in addition to the safety issue, can make confusion to the driver, such that he might pay when he does not have to, or might violate the toll regulations by not payment.
As shown, both of the above two proposed arrangements are not convenient for the driver, and are not safe.
It is therefore an object of the present invention to provide an arrangement that will enable the driver to easily switch the status of the transponder between the “active” and “non active” modes, and to enable him to easily and accurately determine in what mode the transponder is.
It is a further object of the invention to enable said switching and status determination in a most convenience, and safety manner.
Other objects and advantages of the present invention will become apparent as the description proceeds.